Pump Minimum Flow Protection Mode And Introduction

Pump minimum flow protection mode and introduction


There are generally three ways to protect the minimum flow of the pump. They are: (a) design continuous circulation system; (b) design control circulation system; (c) design pump protection valve system. The three protection methods are as follows:

A) Design continuous cycle system

The system diagram is as follows:

centrifugal watr pump 1


① Less investment

② When there is a small flow condition in the process, the flow limiting orifice bypass will automatically eliminate it first.


① No matter how much flow is needed in the process, there is always flow through the side route. The bypass flow shall be added to the operation flow when selecting the pump, otherwise the pump output may be insufficient.

② High operating costs

③ When the head of the pump is very high and the liquid is at saturation temperature, gasification may occur after the orifice of the restriction plate.


B) Design control cycle system

The system diagram is as follows:

centrifugal water pump 2


① Bypass flow added value may not be considered for pump selection

② The bypass can be opened automatically only under the condition of small flow, and closed at ordinary times to save energy.


① The cost of adding a set of automatic control circuit is too high.


C) Design the protection system of self circulation control valve

The system diagram is as follows: 

centrifugal water pump 3


①The automatic circulation control valve automatically recognizes the flow change, automatically opens the main circuit and the bypass circuit, and fully controls

② No other external equipment or component control is required;

③ Cost savings.